1. Field of the Invention
The present invention relates to an air-conditioning method and system used for an automotive vehicle, and more specifically to the air-conditioning method and system in which air temperature at which the passenger compartment is maintained is automatically adjusted to match variations in the passengers' perception of comfortable temperature according to the seasons.
2. Description of the Prior Art
Recently, automotive vehicles have been provided with an air conditioner which can maintain air temperature within the passenger compartment at an appropriate temperature.
In a prior-art air-conditioning system, air is drawn in through an air intake duct by a blower fan and is cooled by a cooling unit. After being cooled, one part of the introduced air is heated by a heating unit and is proportioned with the other unheated part of the introduced air by an air mix door in order to maintain the air within the passenger compartment in a desired temperature. Further, in this case, an air intake door is usually provided in order to selectably effect outside-air introduction or inside-air recirculation. The outside-air introduction mode is used for refreshing the air within the passenger compartment with fresh air and the inside-air recirculation mode is used for cooling or heating the air within the passenger compartment efficiently.
In the air-conditioner as described above, the air mix door is opened or closed by an air mix door actuator, which is controlled by two solenoid valves. The solenoid valves are energized by using a bridge circuit including various resistors of a passenger compartment air temperature sensor, an outside-air temperature sensor, an air mix door opening percentage sensor, a passenger compartment air temperature presetting variable resistor, fixed resistors, etc.
It is well known that the passenger compartment temperature at which a passenger will be comfortable will tend to be a little lower in summer and a little higher in winter. In order to adjust the temperature accordingly in the prior-art air conditioner, it is necessary to change the presetting of the respective comfortable temperature ranges within the passenger compartment in summer and winter by adjusting a temperature presetting lever; however, the required degree of correction is not known to the driver, and also it is troublesome to move the temperature presetting lever in order to re-preset the temperature.
A more detailed description of the prior-art air conditioning system will be made hereinafter with reference to the attached drawings under DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS.